The invention relates to a rotary piston machine, which term includes an internal combustion engine, pump or compressor of either the type having a slant axis or precessing rotor or the type having a parallel axis rotor, the Wankel engine being an example of the latter type.
In either type of machine, the rotor carries a grid of seals which engage internal walls of the housing in which the rotor rotates and which define therein separated working chambers. The portion of the grid bounding each working chamber is usually formed from a plurality of apex seals spaced apart around the rotor axis in a general circumferential direction of the rotor and a plurality of peripheral seals spaced apart in a general direction axially of the rotor. Co-operating peripheral and apex seals are connected together at their adjacent ends by engaging in slots in a connector often called a link block or bolt (and hereinafter called a "bolt") inserted into a socket in the rotor. Although effective sealing is performed between the seals themselves by slotting the circumferential and apex seals in the bolts, there is nevertheless a significant leakage path around each bolt and the wall of its socket. An object of the invention is to provide secondary sealing to reduce leakage around the bolts.